挑战不仅仅是创建应用程序，而是确保它们基于循证实践。

So we beat on, boats against the current, borne back ceaselessly into the past.

There is an awful lot you can tell about a person by their shoes. Where they're going. Where they've been.

量子场论的发展表明，真空不是空的，而是充满了虚粒子。

书，是文字的总扩展。

蓄水池容纳：喷泉溢出。